MLH1 single-nucleotide variant in circulating tumor DNA predicts overall survival of patients with hepatocellular carcinoma.

Liquid biopsy can provide a strong basis for precision medicine. We aimed to identify novel single-nucleotide variants (SNVs) in circulating tumor DNA (ctDNA) in patients with hepatocellular carcinoma (HCC). Deep sequencing of plasma-derived ctDNA from 59 patients with HCC was performed using a panel of 2924 SNVs in 69 genes. In 55.9% of the patients, at least one somatic mutation was detected. Among 25 SNVs in 12 genes, four frequently observed SNVs, MLH1 (13%), STK11 (13%), PTEN (9%), and CTNNB1 (4%), were validated using droplet digital polymerase chain reaction with ctDNA from 62 patients with HCC. Three candidate SNVs were detected in 35.5% of the patients, with a frequency of 19% for MLH1 chr3:37025749T>A, 11% for STK11 chr19:1223126C>G, and 8% for PTEN chr10:87864461C>G. The MLH1 and STK11 SNVs were also confirmed in HCC tissues. The presence of the MLH1 SNV, in combination with an increased ctDNA level, predicted poor overall survival among 107 patients. MLH1 chr3:37025749T>A SNV detection in ctDNA is feasible, and thus, ctDNA can be used to detect somatic mutations in HCC. Furthermore, the presence or absence of the MLH1 SNV in ctDNA, combined with the ctDNA level, can predict the prognosis of patients with HCC.

EC-18, a synthetic monoacetyldiacylglyceride, inhibits hematogenous metastasis of KIGB-5 biliary cancer cell in hamster model.

EC-18 (monoacetyldiacylglyceride) stimulates T cell production of IL-2, IL-4, IL-12, IFN-gamma, and GM-CSF in vitro. To study the effects of these cytokines stimulated by EC-18 on cancer cells, we applied hamster biliary cancer model, a difficult cancer to treat. Cancer (KIGB-5) cells were given intravenously to produce hematogenous metastatic lung lesions which were treated with EC-18 at 10, 25, and 50 mg/kg/day respectively. The fourth group was untreated control. At 4th, 8th, and 12th week the lungs were examined. EC-18 treated groups showed only a few microscopic lung lesions and no evidence of metastatic lesion with highest dose whereas widespread gross lung lesions were observed in untreated control. To investigate whether the anti-tumor effect of EC-18 is associated with suppression of tumor cell Toll-like receptor 4 (TLR-4) expression in addition to stimulation of the immune cells, KIGB-5 cells were exposed to LPS with or without EC-18. TLR-4 mRNA and protein expression, measured by reverse transcriptase PCR (RT-PCR), real-time quantitative PCR and western blot analysis, showed suppression of TLR-4 expression in KIGB-5 cells treated with EC-18 compared with control. In conclusion, EC-18 has a significant anti-tumor effect in this experimental model of biliary cancer suggesting potential for clinical application to this difficult cancer.

Interleukin-2 gene-encoded stromal cells inhibit the growth of metastatic cholangiocarcinomas.

AIM: To demonstrate bone marrow stromal cells (BMSCs) can be used as an attractive target for genetic modification in the treatment of malignant diseases. METHODS: Using a hamster model of biliary cancer, we investigated the therapeutic effects of interleukin-2 (IL-2) gene-modified BMSCs. Syrian golden hamsters were injected via the femoral vein with 5 x 10(5) cells of the KIGB-5 biliary cancer cell line (n=20). One week later, the hamsters were injected intraperitoneally with BMSCs containing Ad/hIL-2 and Ad/ Delta E1, unmodified BMSCs, or RPMI only (control) and observed for 12 wk (n=5 /each group). RESULTS: All hamsters treated with BMSCs containing Ad/hIL-2 survived with no evidence of the disease during this period. In contrast, hamsters in the other three groups showed disseminated metastases involving the lungs as early as 4 wk. CONCLUSION: Ad/IL-2 therapy is effective in the treatment of biliary cancer.